Enhanced upper stratospheric ozone: Sign of recovery or solar cycle effect?

Ozone data measured since 1987 in the 35‐ to 45‐km altitude region by differential absorption laser‐radar (DIAL) at Hohenpeissenberg (47.8°N, 11.0°E) confirm the long‐term ozone decline observed by the satellite‐borne Stratospheric Aerosol and Gas Experiment (SAGE) and Halogen Occultation Experiment (HALOE) instruments, as well as interannual ozone fluctuations. Analysis of the DIAL data indicates that the amplitude of ozone variations related to the 11‐year solar cycle might reach up to 7%, much larger than 4% reported in other studies. Higher ozone values observed in the years 2001 to 2003 might, therefore, be a consequence of the ending solar maximum and not necessarily indicate a beginning recovery of upper stratospheric ozone. Much clearer evidence for a recovery is expected in a few years, near the end of the solar minimum starting now.